Which of the following is a power of the states?

The authority to provide schooling is a power reserved for the states under the U.S. Constitution. This responsibility stems from the Tenth Amendment, which states that powers not delegated to the federal government nor prohibited to the states are reserved for the states or the people. Education is traditionally managed at the state and local levels, allowing for the establishment of school systems that cater to the needs of their respective communities.

This power is significant as it allows each state to tailor its education system according to local circumstances, values, and requirements. For instance, states can set their educational standards, decide on school funding allocations, and determine curriculum requirements. This state control over education reflects the principle of federalism, where certain powers are decentralized to promote local governance.

The other choices—making treaties, declaring war, and creating an army—are powers that are expressly reserved for the federal government. States cannot engage in foreign diplomacy or military action outside the authority given to the federal government, as established by various sections of the Constitution.